In processing signals transported by coaxial cable systems, it is often found that the signal is attenuated by the cable to such an extent that a correction is required to compensate the signal for the cable attenuation. Cable losses may be generally characterized as resistive losses and or dielectric losses. Losses attributed to the resistance value of the cable cause a relatively linear attenuation over the frequency range of the signal being transmitted and is generally not of significant concern. The cable losses attributed to the skin effect of the cable is of major concern as its effect is to attenuate the higher frequencies of the signal being transmitted. The problem of cable attenuation of the signal is further increased as the length of the cables are varied.
Since a fixed cable compensation will not satisfy the typical cable installation, it is common practice to view the signal being received on a waveform monitor and manually switching cable compensation circuits, which may be in the form of high frequency emphasis networks, to compensate for the high frequency losses occurring in the cable. However, as increasingly higher frequency signals are being transported on cable systems, conventional cable equalizing techniques do not provide the proper signal compensation required for telecommunication networks. Therefore, it is desirable to have a cable equalizer that can compensate for attenuation in higher frequency signal transmission.
From the foregoing, it may be appreciated that a need has arisen for a cable equalizer that can flatten out the response inserted into high frequency signals by cable attenuation.